A remotely delivered intervention targeting adults with persisting mild-to-moderate post-concussion symptoms (GAIN Lite): a study protocol for a parallel group randomised trial.

Background: Worldwide, mild traumatic brain injury, synonymous with concussion, affects more than 30-50 million each year. The incidence of concussion in Denmark is estimated to be about 20,000 yearly. Although complete resolution normally occurs within a few weeks, up to a third develop persistent post-concussion symptoms (PPCS) beyond 3 months. Evidence for effective treatment strategies is scarce. The objective of this study is to evaluate the efficacy of the novel intervention GAIN Lite added to enhanced usual care (EUC) for adults with mild-to-moderate PPCS compared to EUC only.

Methods: An open-label, parallel-group, two-arm randomised controlled superiority trial (RCT) with 1:1 allocation ratio. Potential participants will be identified through the hospital's Business Intelligence portal of the Central Denmark Region or referred by general practitioners within 2-4 months post-concussion. Participants with mild-to-moderate PPCS will be randomly assigned to either (1) EUC or (2) GAIN Lite added to EUC. GAIN Lite is characterised as a complex intervention and has been developed, feasibility-tested and process evaluated before effect evaluation in the RCT. GAIN Lite contains an initial remote interview, self-administrated e-learning videos and voluntary remote counselling with an allocated occupational- or physiotherapist. Sixty-six participants will be recruited to each group. Primary outcomes are mean changes in PPCS and limitations in daily life from baseline to 24 weeks after baseline.

Discussion: GAIN Lite is a low-intensity intervention for adults with mild-to-moderate PPCS. Offering a remote intervention may improve access to rehabilitation and prevent chronification for individuals with mild-to-moderate PPCS. Moreover, GAIN Lite will facilitate access to healthcare, especially for those with transportation barriers. Overall, GAIN Lite may provide an accessible, flexible and convenient way to receive treatment based on sound theories and previous evidence of effective interventions for adults with mild-to-moderate PPCS.

Trial Registration: ClinicalTrials.gov NCT05233475. Registered on February 10, 2022.